Lake Ontario

Ontario, which lies on the eastern end of the region, has the smallest surface area of the five Great Lakes. It is 193 miles long and 53 miles wide. Its average depth is 283 feet.  

Ways to Connect

PHOTO: Dan Karpenchuk / Toronto's Port Lands heavily industrialized area slated for redevelopment.

When heavy rains hit Toronto, it’s common for flooding to hit the Port Lands district east of downtown, especially along the Don Valley Parkway. And that can carry untreated waste into Lake Ontario.


Veronica Volk / Great Lakes Today

For the first time in over 50 years, the U.S. and Canada are changing the way they regulate water levels on Lake Ontario. It’s an attempt to meet the changing needs of people who use the lake – from the shipping industry to environmentalists.

But homeowners fear the change may mean more flooding.


Nick Castele/ideastream

In just a few weeks, we’ll have a new presidential administration – and that could mean big changes for the Great Lakes.

Environmental groups are waiting to see how Donald Trump's administration handles issues that are crucial to the region.

Alliance for the Great Lakes

A new study from Rochester Institute of Technology in New York tracks how much plastic is getting into the Great Lakes, and where it's going.

Spoiler alert: There’s lots of it -- in all five lakes.

Lake Ontario Waterkeeper

Environmentalists in Canada are taking a close look at water quality, and a new study by the Lake Ontario Waterkeeper highlights some serious problems.

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